Aeroplane-propeller



a. B. comm. AEROPLANE' PROPELLER.

APPLICATION FILED JULY {5, I918.

1,393,753. Patented 0011.18, 1921.

4 SHEETS-SHEET L G. B. COLUER. AERO PLANE PROPELLER.

APPLICATION FILED JULY [5, 1918.

1,393,753. I Patented 001;. 18, 1921.

4 SHEETS-SHEET 2.

@ m Mu MM MA G. B. COLLIER.

A'EROPLANE PROPELLER.

APPLICATION FILEDJULY 15, 191;.

' 1,393,753. Patented 0m 18, 1921.

4 SHEETS-SHEET 3.

[VIM/V7031 Q B W \XMWAMM e. s. COLLIER.

AEROPLANE PROP ELLER.

APPLICATION FILED JULY 15. 1918.

1,398,753. Patented Oct, 18,1921.

4 SHEETS-SHEET 4.

I rs

TENT QFFICE;

GUY B. COLLIER, KINDEBHOOK, NEW YORK.

AEROPLANE-PBOPELLER,

Application illed July 15, 1918. serial vNo. 244,841.

To all whom it may concern i Be it known that I, GUY B. Coraline, a citizen of the United States residing at Kinderhook, in the county of olumbia and State of New York, have inventedrcertain new and useful Improvements in Aeroplane- Pr-opellers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others. skilled in the art to which it appertains to make and use the same,

The present invention relates to propellers and more particularly to apparatusoi this character designed for" the propulsion of aeroplanes. 7

The existing types of aeroplane propellers now in use are efficient throughout only a comparatively small portion of the blade length and "owing to their design and the peller shown in Fig. 1 and addition the mechanism for p tch of the blades; Fig. 3- 'diagrammatic View illustrating the operat- 111 mechanism for each blade; Fig. 4 is a detail illustrating an elevation of the operatmg mechanism taken upon the line 4-4: of Fig. 2; Fig, 5 is a detail of the mechanism for partially rotating the spider;

illustrating in controlling the Fig. '8 is a section. in elevation of the same pro eller illustrating a modified form of rose anism for varying the pitch of the blades; Fig. is a detail illustrating the operatul g connections for swinging each blade; lgn 8 is a detail taken upon the line 8 -8 of Fig. 6; Fl 9 is a detail taken upon the line v9-9 of ig, 6; Fig 10 is a detail illustrating the rack and pinion mechanism for changing the pitch of the blades; and

she e of the blades cause a severe swirling" g- 11 is a real elfivatioll of the P pe of t e air which seriously detracts from the efficiency of the blade Furthermore these propellers, owing to the absence of any construction for changing the pitch, must necessarily be designed for asingle speed of revolution and decrease. markedly in eificiency at speeds above and below this theoretical best speed-o J I One object of the presentinvention is to improve the construction of propellers more particularly adapted for embodiment in aeroplanes in such a manner that the area of theblades is utilized to the utmost, whi le at the same time minimizing the. eddy cur-= rents and other factors which tend to reduce the efiiciency of the blade,

A further object ofthe invention is to provide for a variation in pitch of the propeller blade between desired limits so that the blades may at all times be pitched at'the angle best suited for any given speed of revolutiomand inaddition enable the speed of the aeroplane to be varied throughout a greater range. 4 1

With these objects in view the several features of the invention consist in certain novel features of construction, combinations and arran ements of parts hereinafter described anclclaimed, the advantagesoit' which will be obvious; to those'skilled inthe art from the following description;

1n the accompanying drawings illustrating the preferred form oi the invention, Figure '1 is arear elevation illustrating clearly the improved propeller honstruction; Fig-"2 isa section in elevation of "the propropellers due to radial flowing of air and a series of blades interposed between the shells and having their leading edges exabout the leading edges to vary the pitch throughmechanism connected to each blade adjacent the discharge edge and designed to move all of the blades synchronously so that the pitch of the several blades shall be the same in all positions. This pitch angle of thevblades may be varied between 30 and degrees and the outer and inner edges of each blade are designed in such a manner that at the minimum pitch angle the outer edge contacts with the external shell and at ,the maximum pitch angle the inner edge contacts with the inner shell, On the other hand, at the minimum pitch angle-the inner edge is at the greatest distance from thecorresponding shell and at the maximum pitch angle the outer edge is at its greatest dis tunes from the corresponding shellq Asthe is a partially tending radially. The blades are swung v swing about the leading edges does not exnular shells a maximum volume of air is di rected against the blade surfaces which are utilized to the utmost capacity. "In the usual construction that portion of the blade extending from the hub of the propeller to a pproximately the position of theinner shell is utilized toa relatively small extent.

The propeller comprises generally an inner shell 20 and an outer shell 21 both of tubular form between which are interposed a series of blades 23. The leading edges of these blades extend radially of the propeller and are-fulcr ed upon shafts 24 se cured at their opposite ends in the inner and outer shells, respectively, as shown in Figs. 1 and 2 of the -drawings. The inner shell is supported at its forward edges by a spider consistin of a series of tubular spokes 26 extendmg from a hub 27 which is provided with an elongated barrel 28. The rear edges of both the inner and outer shells are supported by a spider consisting of a series of tubular spokes 30 extending radially from a hub'31 which is formed upon the rear end of the barrel 28. In order to reduce the resistance offered by the spokes to a minimum each set. of spokes has substantially the form in cross section indicated at 32 in which the leading portion of each spoke tapers to an edge and is set at the mean pitch angle. In order to additionally brace the propeller structure and insurethat it shall be sufiiciently rigid under all con ditions of strain a series of diagonal struts 33 and 34:, respectively, may be provided. The struts 33 extend diagonally from the hub 31 to the front edge of the shell 20 and the diagonal struts 34 extend from the hub 27 to the rear edge of the shell 20. These struts, as indicated in Fig. 2, have substantially the same form in cross section as the spokes of the spider." It will be obvious that this construction presents a compact and rigid form of propeller which affords a minimum resistance to the passage of air therethrough and which utilizes the blade area most effectively. If so desired the outer shell'may be fur'therreinforced by a pair of tubular hoops or bands 35 and 36 which extend about the shell at the, front and rear edges and have approximately the shape indicated in Fig. 2. In addition braces 21" may extend axially of the outer shell betweenthe ends of the spokes 30 and the piv-- otal connections of the blades to brace the propeller fore and aft, as shown clearly in Fig. 2.

pitch may be secured'durin g As stated previously it is highly desirable that the pitch of the blades may be varied within suitable limits to obtain the greatest efliciency from the propeller at varying speeds. To this end mechanism is provided for adjusting the angularity of all of the blades in unison, and for locking the blades in adjusted position, This mechanism in addition is 30 designed that the variation in the continued rotation of the propeller. he sleeve bearing 28 is'mounted upon a rotating propeller Shaft 40 and a shifting frame42 having oppositely disposed arms 43 is splined to the shaft at the rear of the propeller. This shifting shaft is connected to the rear or discharge edges of the blades in such a manner that an axial movement of the frame swings the blades angularly the desired amounts. To this end each one of the 'four arms of the frame is connected at its outer end to the rear portion of a blade through a bell crank lever 44 and connecting link 45. The bell crank, as shown clearly in Figs. 1 and 3, is fulcrumed upona strut 46 extending from one of the spokes 30 and is so designed that a longitudinal or axial movement of the shifting frame swings the connected'blade the desired amount. The move-, ments of the shifting frame are secured through an operating lever 50 fulcrumed upon a stationary stud at 51 and having its lower end connected to a shifting lever 52 through a connecting rod 54. The lever 52 is fulcrumed at 55 upon :1 lug 56 rejecting from a stationary portion of the flame and is provided with a forked upper end 57 the two arms of which are slotted to receive trunnions 59 projecting from the outer stationar housing 60 .of an annular ball hearing. The inner race 61 of the bearing is connected to the shifting frame 42 through a. sleeve 63. As the inner and outer ball races 61 and 60 can not have relative longitudinal movement an oscilla tory movement of the shifting lever 52 imparts a corresponding'movement to the this shifting movetu inal position and to this end-the sleeve 63 is provided with curved slots 68 which receive the opposite ends of a pin 70 extending through the propeller shaft 40. With T this construction when the shiftin frame is I the hub and inner shell.

will be observed that an extremely compact made'to assume different longitu inal posiand eflicient construction has been provlded for varying the pitch of the blades as de-v sired without interfering with the flow of air through the blades or otherwise detract- ,ing from theefliciency.

In order to dlrect the maximum volume of air against the propeller blades the inner and outer shells are provided at their forward edges, respectively, with curved irectinglips 110 and l'llwhich, as shown clearly in Fig. 2, are adapted to collect and of) these shafts is guided at its inner and.

direct the air against the blades during the advancing movement of the propeller. Thls construction assists the stream line flow into the space between the shells and insures an abundance of air for the blades to act upon.

.A'modified construction for changing the pitch of the blades is'indicated in Figs. 7 to 11, inclusive. In this construction an oscillatory shaft 90 extends parallel to each of the spokes 30 and in close proximity thereto and is'provided with an operating arm 91 secured to its outer end which is connected with the rear or discharge ed e of the corresponding blade by a link 92. Jach outer ends in bearing plates 93 and 94 secured to the adjacent spoke 30. By partially rotating all of these shafts in unison the required efficiency of the blades may be secured. To this end a shifting frame, indicated at-95, is provided. This frame has a luralit er to t e number of shafts 90 (in the present case four) extending longitudinally of the propeller shaft 40.' Each; of these arms has formed thereon a series of rack teeth 97 which mesh, respectively, with cooperating to the character of the blade, a shifting arms corresponding in number to the operatof arms" corresponding in *nu'm pinions 98 secured to the inner ends of the shafts 90. Thus it will be seen that an axial movement of the shifting frame 95 through the cooperating racks and pinions rotates the shafts 90 in unison and varies the angularity of the connected blades. The shiftmg frame is connected directly to the inner race 100 of a ball bearing having an outer race 101. A longitudinal movement is imparted to the outer ball race through the same construction described previously and consisting of the operating lever 50, the'connecting rod 54 and the shifting lever 52 having the forked upper end 57 receiving a pair of trunnions 59 which project outwardly from the housing '60 of the ball race 101.

A furthenmodification of the propeller construction is indicated in Figs. 6 and 11 in which the diagonal braces comprise a plurality of short struts 102.which extend, respectively, from opposite ends of the bearing 28 and the front and rear edges of the inner shell to a centrally disposed hub 105, as shown in Fig. 6.

While it is preferred to employ the specific construction and arrangement of parts shown and described, it will be understood that this construction and arran ement is not essential except so far as specified in the claims, and may be changed or modified without departing from the broader features of the invention.

The'invention having been described, what I der supporting the rear edges of the inner and outer shells, and means for simultaneously varying the angularity of all the blades. a

2.'A' propeller comprising a supporting frame, a series of blades mountedupon the frame, an o eratin shaft connected to each raine having a series of ing shafts, a rack formed upon each arm, a pinion secured tothe end of each shaft and meshing with the rack, and means for moving the frame longitudinally to rotate'the shaft and vary the angularity of the blades. j

GUY B. COLLIER. 

